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Audience Effects in Territorial Defense of Male Cichlid Fish Are Associated with Differential Patterns of Activation of the Brain Social Decision-Making Network
Full text linkThis deposit is composed by the main article plus the supplementary materials of the publication.Animals communicate by exchanging signals frequently in the proximity of other conspecifics that may detect and intercept signals not directed to them. There is evidence that the presence of these bystanders modulates the signaling behavior of interacting individuals, a phenomenon that has been named audience effect. Research on the audience effect has predominantly focused on its function rather than on its proximate mechanisms. Here, we have investigated the physiological and neuromolecular correlates of the audience effect in a cichlid fish (Mozambique tilapia, Oreochromis mossambicus). A male was exposed to a territorial intrusion in the presence or absence of a female audience. Results showed that the presence of the female audience increased territorial defense, but elicited a lower androgen and cortisol response to the territorial intrusion. Furthermore, analysis of the expression of immediate early genes, used as markers of neuronal activity, in brain areas belonging to the social decision-making network (SDMN) revealed different patterns of network activity and connectivity across the different social contexts (i.e., audience × intrusion). Overall, these results suggest that socially driven plasticity in the expression of territorial behavior is accommodated in the central nervous system by rapid changes in functional connectivity between nodes of relevant networks (SDMN) rather than by localized changes of activity in specific brain nuclei.Fundação para a Ciência e a Tecnologia post-doc fellowships.info:eu-repo/semantics/publishedVersio
Cognitive appraisal of environmental stimuli induces emotion-like states in fish
Full text linkThis deposit is composed by the main article plus the supplementary materials of the publication.The occurrence of emotions in non-human animals has been the focus of debate over the years. Recently, an interest in expanding this debate to non-tetrapod vertebrates and to invertebrates has emerged. Within vertebrates, the study of emotion in teleosts is particularly interesting since they represent a divergent evolutionary radiation from that of tetrapods, and thus they provide an insight into the evolution of the biological mechanisms of emotion. We report that Sea Bream exposed to stimuli that vary according to valence (positive, negative) and salience (predictable, unpredictable) exhibit different behavioural, physiological and neuromolecular states. Since according to the dimensional theory of emotion valence and salience define a two-dimensional affective space, our data can be interpreted as evidence for the occurrence of distinctive affective states in fish corresponding to each the four quadrants of the core affective space. Moreover, the fact that the same stimuli presented in a predictable vs. unpredictable way elicited different behavioural, physiological and neuromolecular states, suggests that stimulus appraisal by the individual, rather than an intrinsic characteristic of the stimulus, has triggered the observed responses. Therefore, our data supports the occurrence of emotion-like states in fish that are regulated by the individual's perception of environmental stimuli.European Commission grant: (FP7–KBBE-2010-4 Contract n°: 265957 Copewell); Fundação para a Ciência e Tecnologia grants: (SFRH/BD/80029/2011, SFRH/BPD/72952/2010).info:eu-repo/semantics/publishedVersio
Tetranychus urticae mites do not mount an induced immune response against bacteria
Full text linkThe deposited article is a post-print version and has peer review. The deposited article version contains attached the supplementary materials within the pdf. Electronic supplementary material is available online at: https://dx.doi.org/10.6084/m9.figshare.c.3782231. or http://rspb.royalsocietypublishing.org/content/284/1856/20170401.figures-onlyThe genome of the spider mite Tetranychus urticae, a herbivore, is missing important elements of the canonical Drosophila immune pathways necessary to fight bacterial infections. However, it is not known whether spider mites can mount an immune response and survive bacterial infection. In other chelicerates, bacterial infection elicits a response mediated by immune effectors leading to the survival of infected organisms. In T. urticae, infection by either Escherichia coli or Bacillus megaterium did not elicit a response as assessed through genome-wide transcriptomic analysis. In line with this, spider mites died within days even upon injection with low doses of bacteria that are non-pathogenic to Drosophila Moreover, bacterial populations grew exponentially inside the infected spider mites. By contrast, Sancassania berlesei, a litter-dwelling mite, controlled bacterial proliferation and resisted infections with both Gram-negative and Gram-positive bacteria lethal to T. urticae This differential mortality between mite species was absent when mites were infected with heat-killed bacteria. Also, we found that spider mites harbour in their gut 1000-fold less bacteria than S. berlesei We show that T. urticae has lost the capacity to mount an induced immune response against bacteria, in contrast to other mites and chelicerates but similarly to the phloem feeding aphid Acyrthosiphon pisum Hence, our results reinforce the putative evolutionary link between ecological conditions regarding exposure to bacteria and the architecture of the immune response.Marie Sklodowska-Curie Action (MSCA) grant: (658795-DOGMITE); Horizon 2020; Fund for Scientific Research Flanders grants: (G009312N, G053815N); EC contract grant: (618105); FACCE ERA-NET Plus FACCE-JP grant: (Genomite, project ID 137 via NWO); Instituto Gulbenkian de Ciência/Fundação Calouste Gulbenkian; Fundação para a Ciência e a Tecnologia grant: (ANR/BIA-EVF/0013/2012, FCT-TUBITAK/0001/2014); Government of Canada through Genome Canada and the Ontario Genomics Institute grants: (OGI-046); Ontario Research Fund – Global Leadership in Genomics and Life Sciences grant: (GL2-01-035); NSERC Strategic Grant: (STPGP322206-05); JGI Community Sequencing Program grant: (777506).info:eu-repo/semantics/publishedVersio
Tolerogenic insulin peptide therapy precipitates type 1 diabetes
Full text linkThis deposit is composed by the main article plus the supplementary materials of the publication.Daniel et al. (https://doi.org/10.1084/jem.20110574) have previously published in JEM a study on the preventive effect of tolerogenic vaccination with a strong agonist insulin mimetope in type 1 diabetes. Our study now challenges these results and shows that osmotic pump delivery of the modified insulin peptide R22E did not prevent hyperglycemia, accelerated disease onset, increased its incidence, and worsened insulitis.Further funders are not indicated in the document.info:eu-repo/semantics/publishedVersio
Myocardial aging as a T-cell–mediated phenomenon
No full textThis deposit is composed by a publication in which the IGC's authors have had the role of collaboration (it's a collaboration publication). This type of deposit in ARCA is in restrictedAccess (it can't be in open access to the public), and can only be accessed by two ways: either by requesting a legal copy from the author (the email contact present in this deposit) or by visiting the following link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5373357/This publication hasn't any creative commons license associated.In recent years, the myocardium has been rediscovered under the lenses of immunology, and lymphocytes have been implicated in the pathogenesis of cardiomyopathies with different etiologies. Aging is an important risk factor for heart diseases, and it also has impact on the immune system. Thus, we sought to determine whether immunological activity would influence myocardial structure and function in elderly mice. Morphological, functional, and molecular analyses revealed that the age-related myocardial impairment occurs in parallel with shifts in the composition of tissue-resident leukocytes and with an accumulation of activated CD4+Foxp3-(forkhead box P3) IFN-γ+T cells in the heart-draining lymph nodes. A comprehensive characterization of different aged immune-deficient mouse strains revealed that T cells significantly contribute to age-related myocardial inflammation and functional decline. Upon adoptive cell transfer, the T cells isolated from the mediastinal lymph node (med-LN) of aged animals exhibited increased cardiotropism, compared with cells purified from young donors or from other irrelevant sites. Nevertheless, these cells caused rather mild effects on cardiac functionality, indicating that myocardial aging might stem from a combination of intrinsic and extrinsic (immunological) factors. Taken together, the data herein presented indicate that heart-directed immune responses may spontaneously arise in the elderly, even in the absence of a clear tissue damage or concomitant infection. These observations might shed new light on the emerging role of T cells in myocardial diseases, which primarily affect the elderly population.Bundesministerium für Bildung und Forschung grants: (BMBF01, EO1004); German Research Foundation grant: (DFG SFB688, TP A10, and B07); Brazilian National Council for Scientific and Technological Development.info:eu-repo/semantics/publishedVersio
Beyond killing: Can we find new ways to manage infection?
Full text linkThis deposit is composed by the main article, and hasn't not associated any supplementary materials of the publication.The antibiotic pipeline is running dry and infectious disease remains a major threat to public health. An efficient strategy to stay ahead of rapidly adapting pathogens should include approaches that replace, complement or enhance the effect of both current and novel antimicrobial compounds. In recent years, a number of innovative approaches to manage disease without the aid of traditional antibiotics and without eliminating the pathogens directly have emerged. These include disabling pathogen virulence-factors, increasing host tissue damage control or altering the microbiota to provide colonization resistance, immune resistance or disease tolerance against pathogens. We discuss the therapeutic potential of these approaches and examine their possible consequences for pathogen evolution. To guarantee a longer half-life of these alternatives to directly killing pathogens, and to gain a full understanding of their population-level consequences, we encourage future work to incorporate evolutionary perspectives into the development of these treatments.Wellcome Trust for the Centre for Immunity, Infection and Evolution grant: (095831); ETH Zürich fellowship: (Society in Science—Branco Weiss); Human Frontier Science Programme grant: (HFSP RGP0011/2014); Fundação Calouste Gulbenkian; Fundação para a Ciência e Tecnologia grants: (PTDC/SAU TOX/116627/2010, HMSP-ICT/0022/2010); ERC 7th Framework grant: (ERC-2011-AdG.294709-DAMAGECONTROL); BSRC Institute Strategic Programme grant: (ISP1); Swiss National Science Foundation grant: (PP00P3-139164); Novartis Foundation for medical and biological research.info:eu-repo/semantics/publishedVersio
Genetics of host-parasite interactions: towards a comprehensive dissection of Drosophila resistance to viral infection
Full text linkThe deposited article is a post-print version and has peer-review. There are no funders and sponsors indicated explicitly in the document. There is no public supplementary material available. This publication hasn't any creative commons license associated.One of the major challenges in evolutionary biology is to unravel the genetic basis of adaptation. This issue has been gaining momentum in recent years with the accelerated development of novel genetic and genomic techniques and resources. In this issue of Molecular Ecology, Cogni et al. (2016) address the genetic basis of resistance to two viruses in Drosophila melanogaster using a panel of recombinant inbred lines with unprecedented resolution allowing detection of rare alleles and/or alleles of small effect. The study confirms the role of previously identified genes of major effect and adds novel regions with minor effect to the genetic basis of Drosophila resistance to the Drosophila C virus or the sigma virus. Additional analyses reveal the absence of cross-resistance and of epistasis between the various genomic regions. This detailed information on the genetic architecture of host resistance constitutes an important step towards the understanding of both the physiology of antiviral immunity and the evolution of host-parasite interactions.There are no funders and sponsors indicated explicitly in this uploaded article version.info:eu-repo/semantics/publishedVersio
Social Plasticity Relies on Different Neuroplasticity Mechanisms across the Brain Social Decision-Making Network in Zebrafish
Full text linkSocial living animals need to adjust the expression of their behavior to their status within the group and to changes in social context and this ability (social plasticity) has an impact on their Darwinian fitness. At the proximate level social plasticity must rely on neuroplasticity in the brain social decision-making network (SDMN) that underlies the expression of social behavior, such that the same neural circuit may underlie the expression of different behaviors depending on social context. Here we tested this hypothesis in zebrafish by characterizing the gene expression response in the SDMN to changes in social status of a set of genes involved in different types of neural plasticity: bdnf, involved in changes in synaptic strength; npas4, involved in contextual learning and dependent establishment of GABAergic synapses; neuroligins (nlgn1 and nlgn2) as synaptogenesis markers; and genes involved in adult neurogenesis (wnt3 and neurod). Four social phenotypes were experimentally induced: Winners and Losers of a real-opponent interaction; Mirror-fighters, that fight their own image in a mirror and thus do not experience a change in social status despite the expression of aggressive behavior; and non-interacting fish, which were used as a reference group. Our results show that each social phenotype (i.e., Winners, Losers, and Mirror-fighters) present specific patterns of gene expression across the SDMN, and that different neuroplasticity genes are differentially expressed in different nodes of the network (e.g., BDNF in the dorsolateral telencephalon, which is a putative teleost homolog of the mammalian hippocampus). Winners expressed unique patterns of gene co-expression across the SDMN, whereas in Losers and Mirror-fighters the co-expression patterns were similar in the dorsal regions of the telencephalon and in the supracommissural nucleus of the ventral telencephalic area, but differents in the remaining regions of the ventral telencephalon. These results indicate that social plasticity relies on multiple neuroplasticity mechanisms across the SDMN, and that there is not a single neuromolecular module underlying this type of behavioral flexibility.FCT fellowships: (SFRH/BD/44848/2008, SFRH/BD/89072/2012)
The immunity-related GTPase Irga6 dimerizes in a parallel head-to-head fashion
Full text linkThe immunity-related GTPases (IRGs) constitute a powerful cell-autonomous resistance system against several intracellular pathogens. Irga6 is a dynamin-like protein that oligomerizes at the parasitophorous vacuolar membrane (PVM) of Toxoplasma gondii leading to its vesiculation. Based on a previous biochemical analysis, it has been proposed that the GTPase domains of Irga6 dimerize in an antiparallel fashion during oligomerization.Leibniz Graduate School grants: (SFB958, SFB635)
Transcriptomic and metabolomic profiling of ionic liquid stimuli unveils enhanced secondary metabolism in Aspergillus nidulans
Full text linkThe inherent potential of filamentous fungi, especially of Ascomycota, for producing diverse bioactive metabolites remains largely silent under standard laboratory culture conditions. Innumerable strategies have been described to trigger their production, one of the simplest being manipulation of the growth media composition. Supplementing media with ionic liquids surprisingly enhanced the diversity of extracellular metabolites generated by penicillia. This finding led us to evaluate the impact of ionic liquids' stimuli on the fungal metabolism in Aspergillus nidulans and how it reflects on the biosynthesis of secondary metabolites (SMs).European Research Council grant: (ERC-2014-CoG-647928); Spanish Ministry of Economy and Competitiveness project: (CTQ2012-30836); Agency for Administration of University and Research Grants (Generalitat de Catalunya, Spain) project: (2014 SGR-539); COST Action EXIL – Exchange on Ionic Liquids: (CM1206); FCT fellowships and contract grant: (SFRH/BD/66030/2009, SFRH/BPD/110841/2015, IF/00713/2013)